Archives of Enviornmental Contamination and Toxicology
Medicago sativa L. (Leguminosae) sprayed with O,O-dimeth-yl S-(N-methylcarbamoylmethyl) phosphorodithioate (dimethoate) had only 0.5 ppm of dimethoate in pollen one day later, but 3 ppm in nectar one week later, and 1 ppm in nectar two weeks later. As little as 1 ppm added to syrup fed to caged workers of Apis mellifera L. (Apidae) inhibited cholinesterase and reduced survival. Bees given a choice between treated and untreated syrups showed no preference; this suggests that the levels of dimethoate found in nectar are toxic and not repellent.
Barker, Roy J.; Lehner, Yolanda; and Kunzmann, Michael R., "Pesticides and Honey Bees: Nectar and Pollen Contamanation in Alfalfa Treated with Dimethoate" (1980). An. Paper 220.
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